Chapter 4, Hemodynamic disorders, Thromboembolism, and shock Flashcards
defined hemostasis?
blood clotting
thrombosis definition?
inappropriate clotting
Embolism definition?
migration of clots which could cause ischemic cell death (infraction)
Hyperemia definition?
active process resulting from arteriolar dilation and increased blood inflow (inflammation or exercising muscle)
tissue appears redder due to oxygenated blood.
Congestion definition?
passive process resulting from impaired outflow of venous blood from tissues. (cardiac failure or local obstruction)
tissue appears blue due to deoxy-blood (cyanosis).
name that is used to describe fluid accumulation in pleural cavity, pericardial cavity, or the peritoneal cavity
- pleural cavity (hydrothorax)
- pericardial cavity (hydropericardium)
- peritoneal cavity (hydroperitoneum or ascites)
definition of Anasarca?
a severed, generalized edema marked by profound swelling of subcutaneous tissues and accumulation of fluid in body cavities.
the does the vicious cycle of fluid retention occur during edema?
increased venous hydrostatic pressure in patients with congestive heart failure. The reduced cardiac output results in hypoperfusion of the kidneys, triggering the renin-angiotensin-aldosterone axis, increasing blood volume that the failing heart may not be able to compensate for. thus edema worsens.
causes of Edema?
- increased hydrostatic pressure (heart failure)
- reduced plasma osmotic pressure (low albumin)
- lymphatic obstruction
- Sodium and water retention
what are the causes of reduced plasma osmotic pressure?
reduced Albumin concentration which makes up upto half of the proteins in the blood.
- Nephrotic syndrome: leaky glomerular capillaries causes albumin and protein loss.
- Reduced albumin synthesis (liver disease)
define pitting edema
when a finger is used to apply pressure to an edema causing a finger-shaped depression.
define hemorrhagic diatheses
clinical disorders increasing the risk of hemorrhage.
extensive hemorrhage can result in jaundice from the massive RBC breakdown.
define hemarthrosis
accumulation of blood in the joints.
Petechiae definition?
1-2mm diameter hemorrhages into the skin, mucous membranes or serosal surfaces (low platelet count, defective platelet function, loss of vascular wall support due to low vitamin C.
purpura definition?
a larger 3-5mm hemorrgaes (caused by trauma, vascular inflammation, and also the same disorders as petechiae.
ecchymoses definition?
subcutaneous hematomas (a bruise)
why does internal bleeding not lead to iron deficiency?
internal blood loss, the RBC are phagocytosed and the iron is efficiently recycled.
Glanzmann thrombasthenia
bleeding disorder caused by GP IIBb/IIIa in platelets.
what does Coumadin do?
antagonizes the enzymatic reaction that produce y-carboxylated glutamic acid using vitamin K as cofactor, it is a widely used anti-coagulant.
prothrombin time tests what?
assesses the function of the proteins in the EXTRINSIC pathway.
Partial thromboplastin time (PTT) test what?
Intrinsic pathway proteins function.
function of Thrombin?
- conversion of fibrinogen into crosslinked fibrin
- platelet activation (via PAR protease activated receptor)
- proinflammatory effects
- anti-coagulant effects
3 methods to prevent the coagulation plug from spreading from the site of injury?
1: the blood washes out the pro-coagulant factors
2: the negative charges on platelet surface is limited to site injury
3: the anticoagulant factors expressed adjacent to site of injury. (plasminogen made into plasmin via XII and tPA) a2-plasmin inhibitor, inhibits free plasmin.
3 methods to prevent the coagulation plug from spreading from the site of injury?
1: the blood washes out the pro-coagulant factors
2: the negative charges on platelet surface is limited to site injury
3: